RFC 3264, "An Offer/Answer Model with Session Description Protocol (SDP)", June 2002

Errata ID: 5177
Status: Reported
Type: Technical
Publication Format(s) : TEXT
Reported By: Sandeep Kumar Aitha
Date Reported: 2017-11-03

Section 5.1 says:

Section 5.1 says:
However, for sendonly and sendrecv streams, the answer might indicate
different payload type numbers for the same codecs, in which case,
the offerer MUST send with the payload type numbers from the answer.

Section 6.2 says:
In the case of RTP, if a particular codec was referenced with a
specific payload type number in the offer, that same payload type
number SHOULD be used for that codec in the answer.

It should say:

Only one of the above statements can be correct.

Notes:

Above two statements are conflicting.
The answerer should be able to either map the payload type to a different codec or not.

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